Feit Electric 18-Watt Equivalent PL CFLNI Quad Tube 4-Pin G24Q-2 Base Compact Fluorescent CFL Light Bulb, Soft White 2700K (1-Bulb) BPPLD18E/HDRP - The Home Depot
Simply Conserve 13-Watt Equivalent CFLNI Horizontal G24Q PL LED Light Bulb in Cool White (20-Pack) L9PL40G24QH - The Home Depot
Simply Conserve G24Q/GX24Q horizontal PL 18-Watt EQ Single tube Daylight Gx24q-4 Pin Base LED Light Bulb (20-Pack) in the General Purpose LED Light Bulbs department at Lowes.com
REPLACEMENT BULB FOR PHILIPS PL-C 18W/827/4P 18W | eBay
Lustaled Gx24 4-Pin Base LED Bulb, 12W G24q PL-C | Ubuy UK
Feit Electric 13W/18W/26W Equivalent PL Horizontal 4-Pin Universal Base G24Q/GX24Q-1/-2/-3 CCT Select(2700K/3500K/4100K)LED Light Bulb PL26A/H/CCT/ LED/HDRP - The Home Depot
REPLACEMENT BULB FOR PHILIPS PL-C 18W/827/4P 18W | eBay